Rock RQD 1

[Geokhan]

Hi. Some days when we are coring in rocks,sometime mudstone and muddy material get stuck in the core tube as a result the opperatore open the tube along with the core sample inside. They tried hard to get out the core from tube at this process they hit the tube on ground due to which the core sample comes out at broken pieces and the whole mudstone and siltstone become broken.. In such cases how to calculate the RQD and SCR for report. And also tell me about the standard way to pull out such stuck cores. Thanks in advanced

 

[GeoEnvGuy]

Two thoughts if the material is intact you can look for weathering in the broken core and reconstruct it to say its a mechanical break of intact core. The second train of thought is that if the material crumbles getting it out of the tube this represents how it will perform when excavating.

For emptying the tube ensure enough water flushes the hole clear and it should slide out and if the material is to fractured and causes issues drilling nevermind emptying the tube you can use a split tube that unscrews the top and bottom similar to a split spoon.